In a Philadelphia courtroom not far from where Junior Seau once scored a touchdown for the Chargers, NFL lawyers are arguing to dismiss a brain injury lawsuit filed on behalf of more than 4,000 ex-players and some of their families, Seau’s included.

U.S. District Judge Anita Brody will weigh the league’s claim that the disputes belong in arbitration, under terms of the collective bargaining agreement. Her ruling, expected in weeks if not months, could come before another helmet-banging NFL season begins in September.

Plaintiff lawyers are suing for billions of dollars on the ground the NFL “deliberately ignored and actively concealed” information about concussions for decades.

If Brady rules in favor of the players, the dispute will remain public and lawyers could seek NFL medical files, in addition to deposing league officials.

A ruling for the NFL would, in effect, kick all of the players’ claims out of court and into arbitration.

“An arbitrator would basically say, ‘No, there is no breach of contract here, these players’ grievances, there’s nothing to them,’ ” said Paul D. Anderson, a Kansas City attorney who runs an independent Web site, nflconcussionlitigation.com, to track concussion-related news.

Seau, a former linebacker and 12-time Pro Bowler who helped the Chargers reach a Super Bowl, died last May of a self-inflicted gunshot wound at his beachfront home in Oceanside.

Seau’s former wife, Gina, said she believes Seau suffered numerous concussions during his 20-year career. Employed also by the Dolphins and Patriots, Seau never appeared on an NFL-released injury report with a concussion.

His survivors, in two wrongful death lawsuits, allege that throughout his career he sustained violent hits that caused traumatic brain injury, depression and ultimately his death at age 43.

Those lawsuits were folded into the larger suit against the NFL.

Seau was diagnosed with a degenerative brain disease, chronic traumatic encephalopathy, or CTE, after his death.

His survivors’ complaint also accuses the NFL of glorifying violence on the field.

“This success comes at a price to the players who make the game great,” Seau’s parents, Tiaina Sr. and Luisa Seau, said in their lawsuit.

Seau’s four children are represented in the other suit.

Anderson said that if the larger lawsuit results in neither arbitration nor a settlement, it may be “several years,” if then, before the Seau family’s two lawsuits would reach trial. The proceeding would be in front of a San Diego County judge and jury.

Should the Seau lawsuits advance that far, medical experts would take center stage.

“The NFL’s medical experts, they’ll be saying one thing: his death was not caused, or contributed to in any way, by football,” Anderson said. “Junior Seau’s family, their medical experts – they’ll say that the repetitive trauma that Seau was exposed to, throughout his 20 years, led to his death."

Anderson said the Seau legal team would face “a very tremendous and difficult burden” of proof.

In Philadelphia, Brady will hear NFL arguments that a legal doctrine known as “pre-emption” should prevail. If she agrees, the dispute is pre-empted by the collective bargaining agreements and must be submitted to arbitratrion.

It’s a legal argument that has worked for the NFL in other disputes, wrote ESPN legal analyst Lester Munson, but it might not work in the concussion case. The reason for that is a rule of law established in Kline vs. Security Guards, Inc.

Anderson said he sees the NFL’s current legal position as a vulnerable one, but said he’s not ruling out a “long litigation battle for the next several years.”

Notable among the league's defenders in the court of public opinion is a former player, Hall of Famer Deion Sanders. He depicted the concussion lawsuit as a money grab by some, but not all, ex-players.

“I think the litigation has already benefited society as a whole,” Anderson said. “People have their own thoughts about lawsuits, but I think this lawsuit has increased awareness tenfold about concussions. I think that’s the best thing that has occurred."